1. RR: How many ways can you count to 100?

2. Do you know how to count? In chemistry, the unit that helps us count is the mole (mol). The mole represents 6.022 x 10 23 pieces of something. 6.022 x 10 23 = 602,200,000,000,000,000,000,000 called Avogadro’s number In chemistry, our pieces are atoms, particles, ions, molecules, etc. We can express the mole mathematically as a conversion factor – a mathematical ratio used to express a relationship between different units.

3. Avogadro’s Number and the Mole

4. RR: How many atoms are in 1.0 mole of carbon?

5. Known (what you have) Unknown (what you need) Relationship (conversion factor) Shown Work Answer

6. RR: How many atoms of oxygen are in 1 mole of glucose, C 6 H 12 O 6 ?

7. Mass and the Mole Atomic mass units are based on the mass of carbon’s most common isotope, C—12. Most of the time, chemists use grams to measure mass. Each element’s mass is located on the periodic table. We can find the molar mass (mass per mole) of each element by dividing the mass of the element by the moles of the element. For a single mole of an element, the mass is the same as the mass on the periodic table. Example: What is Carbon’s molar mass?

8. Molar Mass of a Molecule or Compound If we know the number of moles of each element, we can find the total mass of a molecule by adding together the molar masses of each element. Note, moles ≠ atoms

9. Question 1: How many atoms of oxygen are in 1 mole of glucose, C 6 H 12 O 6 ? Question 2: How many atoms of oxygen are in 1 molecule of glucose, C 6 H 12 O 6 ? Note the difference in the two questions.

10. RR: How many atoms of oxygen are in 1 mole of glucose, C 6 H 12 O 6 ? Think of the relationship between oxygen and glucose. How many oxygens are there per glucose molecule? How can you relate the oxygen number to atoms? (think of a conversion factor) How could you calculate the molar mass of the glucose? What is the mass of oxygen? What is the mass of oxygen in 1.0 mol glucose? What else makes up glucose?

11. How many atoms of oxygen are in 1 molecule of glucose, C 6 H 12 O 6 ? Note, we are not comparing atoms to moles this time!